Azure AI OpenAI chat GPT-4 client connection

This article presents code that shows how you can connect to OpenAI Chat GPT-4 client connection. The repository for the code presented is the following GitHub repo:

https://github.com/toreaurstadboss/OpenAIDemo

The repo contains useful helper methods to use Azure AI Service and create AzureOpenAIClient or the more generic ChatClient which is a specified chat client for the AzureOpenAIClient that uses a specific ai model, default ai model to use is 'gpt-4'. The creation of chat client is done using a class with a builder pattern. To create a chat client you can simply create it like this :

Program.cs

         const string modelName = "gpt-4";

            var chatClient = AzureOpenAIClientBuilder
                .Instance
                .WithDefaultEndpointFromEnvironmentVariable()
                .WithDefaultKeyFromEnvironmentVariable()
                .BuildChatClient(aiModel: modelName);
                

The builder looks like this:

AzureOpenAIClientBuilder.cs

using Azure.AI.OpenAI;
using OpenAI.Chat;
using System.ClientModel;

namespace ToreAurstadIT.OpenAIDemo
{

    /// <summary>
    /// Creates AzureOpenAIClient or ChatClient (default model is "gpt-4")
    /// Suggestion:
    /// Create user-specific Environment variables for : AZURE_AI_SERVICES_KEY and AZURE_AI_SERVICES_ENDPOINT to avoid exposing endpoint and key in source code.
    /// Then us the 'WithDefault' methods to use the two user-specific environment variables, which must be set.
    /// </summary>
    public class AzureOpenAIClientBuilder
    {

        private const string AZURE_AI_SERVICES_KEY = nameof(AZURE_AI_SERVICES_KEY);
        private const string AZURE_AI_SERVICES_ENDPOINT = nameof(AZURE_AI_SERVICES_ENDPOINT);

        private string? _endpoint = null;
        private ApiKeyCredential? _key = null;

        public AzureOpenAIClientBuilder WithEndpoint(string endpoint) { _endpoint = endpoint; return this; }

        /// <summary>
        /// Usage: Provide user-specific enviornment variable called : 'AZURE_AI_SERVICES_ENDPOINT'
        /// </summary>
        /// <returns></returns>
        public AzureOpenAIClientBuilder WithDefaultEndpointFromEnvironmentVariable() { _endpoint = Environment.GetEnvironmentVariable(AZURE_AI_SERVICES_ENDPOINT, EnvironmentVariableTarget.User); return this; }
       
        
        public AzureOpenAIClientBuilder WithKey(string key) { _key = new ApiKeyCredential(key); return this; }       
        public AzureOpenAIClientBuilder WithKeyFromEnvironmentVariable(string key) { _key = new ApiKeyCredential(Environment.GetEnvironmentVariable(key) ?? "N/A"); return this; }

        /// <summary>
        /// Usage : Provide user-specific environment variable called : 'AZURE_AI_SERVICES_KEY'
        /// </summary>
        /// <returns></returns>
        public AzureOpenAIClientBuilder WithDefaultKeyFromEnvironmentVariable() { _key = new ApiKeyCredential(Environment.GetEnvironmentVariable(AZURE_AI_SERVICES_KEY, EnvironmentVariableTarget.User) ?? "N/A"); return this; }

        public AzureOpenAIClient? Build() => !string.IsNullOrWhiteSpace(_endpoint) && _key != null ? new AzureOpenAIClient(new Uri(_endpoint), _key) : null;

        /// <summary>
        /// Default model will be set 'gpt-4'
        /// </summary>
        /// <returns></returns>
        public ChatClient? BuildChatClient(string aiModel = "gpt-4") => Build()?.GetChatClient(aiModel);

        public static AzureOpenAIClientBuilder Instance => new AzureOpenAIClientBuilder();

    }
}

It is highly recommended to store your endpoint and key to the Azure AI service of course not in the source code repository, but another place, for example on your user-specific environment variable or Azure key vault or similar place hard to obtain for malicious use, for example using your account to route much traffic to Chat GPT-4 only to end up being billed for this traffic. The code provided some 'default methods' which will look for environment variables. Add the key and endpoint to your Azure AI to these user specific environment variables.

• AZURE_AI_SERVICES_KEY
• AZURE_AI_SERVICES_ENDPOINT

To use the chat client the following code shows how to do this:

ChatGptDemo.cs

    public async Task<string?> RunChatGptQuery(ChatClient? chatClient, string msg)
        {
            if (chatClient == null)
            {
                Console.WriteLine("Sorry, the demo failed. The chatClient did not initialize propertly.");
                return null;
            }

            var stopWatch = Stopwatch.StartNew();

            string reply = await chatClient.GetStreamedReplyStringAsync(msg, outputToConsole: true);

            Console.WriteLine($"The operation took: {stopWatch.ElapsedMilliseconds} ms");


            Console.WriteLine();

            return reply;
        }
        
        

The communication against Azure AI service with Open AI Chat-GPT service is this line:

ChatGptDemo.cs

    string reply = await chatClient.GetStreamedReplyStringAsync(msg, outputToConsole: true);

The Chat GPT-4 service will return the data streamed so you can output the result as quickly as possible. I have tested it out using Standard Service S0 tier, it is a bit slower than the default speed you get inside the browser using Copilot, but it works and if you output to the console, you get a similar experience. The code here can be used in different environments, the repo contains a console app with .NET 8.0 Framework, written in C# as shown in the code. Here is the helper methods for the ChatClient, provided as extension methods.

ChatclientExtensions.cs

using OpenAI.Chat;
using System.ClientModel;
using System.Text;

namespace OpenAIDemo
{
    public static class ChatclientExtensions
    {

        /// <summary>
        /// Provides a stream result from the Chatclient service using AzureAI services.
        /// </summary>
        /// <param name="chatClient">ChatClient instance</param>
        /// <param name="message">The message to send and communicate to the ai-model</param>
        /// <returns>Streamed chat reply / result. Consume using 'await foreach'</returns>
        public static AsyncCollectionResult<StreamingChatCompletionUpdate> GetStreamedReplyAsync(this ChatClient chatClient, string message) =>
            chatClient.CompleteChatStreamingAsync(
                [new SystemChatMessage("You are an helpful, wonderful AI assistant"), new UserChatMessage(message)]);

        public static async Task<string> GetStreamedReplyStringAsync(this ChatClient chatClient, string message, bool outputToConsole = false)
        {
            var sb = new StringBuilder();
            await foreach (var update in GetStreamedReplyAsync(chatClient, message))
            {
                foreach (var textReply in update.ContentUpdate.Select(cu => cu.Text))
                {
                    sb.Append(textReply);
                    if (outputToConsole)
                    {
                        Console.Write(textReply);
                    }
                }
            }
            return sb.ToString();
        }

    }
}

The code presented here should make it a bit easier to communicate with the Azure AI Open AI Chat GPT-4 service. See the repository to test out the code. Screenshot below shows the demo in use in a console running against the Azure AI Chat GPT-4 service :